Standard Test Method for Evaluation of Recoverable Stretch of Stretch Yarns (Skein Method)

Importancia y uso:

5.1 This test method is considered satisfactory for acceptance testing of commercial shipments because current estimates of between-laboratory precision are acceptable and the method is used extensively in the trade for acceptance testing.

5.1.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use samples for such comparative tests that are as homogeneous as possible, drawn from the same lot of material as the samples that resulted in disparate results during initial testing, and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.

5.2 This test differs from other crimp contraction test methods in that it measures the recoverable stretch during the unload cycle of the yarn.

Subcomité:

D13.58

Volúmen:

07.02

Número ICS:

59.080.20 (Yarns)

Palabras clave:

crimp; elastomeric yarns; recoverable stretch; stretch yarns; textured yarns;